Idiolects

Idiolect is an individual's distinctive and unique use of language, including speech. This unique usage encompasses vocabulary, grammar, and pronunciation.

Idiolect is the variety of language unique to an individual. This differs from a dialect, a common set of linguistic characteristics shared among some group of people.

The notion of language is used as an abstract description of the language use, and of the abilities of individual speakers and listeners. According to this view, a language is an "ensemble of idiolects . . . rather than an entity per se." Linguists study particular languages, such as English or Xhosa, by examining the utterances produced by the people who speak the language.

This contrasts with a view among non-linguists, at least in the United States, that languages as ideal systems exist outside the actual practice of language users. Based on work done in the US, Nancy Niedzielski and Dennis Preston describe a language ideology that appears to be common among American English speakers. According to Niedzielski and Preston, many of their subjects believe that there is one "correct" pattern of grammar and vocabulary that underlies Standard English, and that individual usage derives from this external system.

Linguists who understand particular languages as a composite of unique, individual idiolects must nonetheless account for the fact that members of large speech communities, and even speakers of different dialects of the same language, can understand one another. All human beings seem to produce language in essentially the same way. This has led to searches for universal grammar, as well as attempts to further define the nature of particular languages.

The scope of forensic linguistics includes attempts to identify whether a certain person did or did not produce a given text by comparing the style of the text with the idiolect of the individual. The forensic linguist may conclude that the text is consistent with the individual, rule out the individual as the author, or deem the comparison inconclusive.

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